Osteichthyes

Osteichthyes (/ˌɒstiˈɪkθiiːz/), popularly referred to as the bony fish, is a diverse taxonomic group of fish that have skeletons primarily composed of bone tissue, as opposed to cartilage. The vast majority of fish are members of Osteichthyes, which is an extremely diverse and abundant group consisting of 45 orders, and over 435 families and 28,000 species.[1] It is the largest class of vertebrates in existence today. The group Osteichthyes is divided into the ray-finned fish (Actinopterygii) and lobe-finned fish (Sarcopterygii). The oldest known fossils of bony fish are about 420 million years old, which are also transitional fossils, showing a tooth pattern that is in between the tooth rows of sharks and bony fishes.[2]

Osteichthyes can be compared to Euteleostomi. In paleontology, the terms are synonymous. In ichthyology, the difference is that Euteleostomi presents a cladistic view which includes the terrestrial tetrapods that evolved from lobe-finned fish, whereas prior to 2014 the view of most ichthyologists was that Osteichthyes includes only fishes, and were therefore paraphyletic. However, in 2014, an ichthyology paper was published with phylogenetic trees that treat the Osteichthyes as a clade including tetrapods.[3]

Osteichthyes
Temporal range: 420–0 Ma
Blue runner
Blue runner
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Clade: Teleostomi
Superclass: Osteichthyes
Huxley, 1880
Groups included
Cladistically included but traditionally excluded taxa

Characteristics

Guiyu BW
Guiyu oneiros, the earliest known bony fish, lived during the Late Silurian, 419 million years ago).[4][5] It has the combination of both ray-finned and lobe-finned features, although analysis of the totality of its features place it closer to lobe-finned fish.[6][7][8]

Bony fish are characterized by a relatively stable pattern of cranial bones, rooted, medial insertion of mandibular muscle in the lower jaw. The head and pectoral girdles are covered with large dermal bones. The eyeball is supported by a sclerotic ring of four small bones, but this characteristic has been lost or modified in many modern species. The labyrinth in the inner ear contains large otoliths. The braincase, or neurocranium, is frequently divided into anterior and posterior sections divided by a fissure.

Early bony fish had simple lungs (a pouch on either side of the esophagus) which helped them breathe in low-oxygen water. In many bony fish these have evolved into swim bladders, which help the body create a neutral balance between sinking and floating. (The lungs of amphibians, reptiles, birds, and mammals were inherited from their bony fish ancestors.)[9][10][11] They do not have fin spines, but instead support the fin with lepidotrichia (bone fin rays). They also have an operculum, which helps them breathe without having to swim.

Bony fish have no placoid scales. Mucus glands coat the body. Most have smooth and overlapping ganoid, cycloid or ctenoid scales.

Classification

Traditionally, Osteichthyes is considered a class, recognised on having a swim bladder, only three pairs of gill arches, hidden behind a bony operculum and a predominately bony skeleton.[12] Under this classification systems, the Osteichthyes are paraphyletic with regard to land vertebrates as the common ancestor of all Osteichthyes includes tetrapods amongst its descendants. The largest subclass, the Actinopterygii (ray-finned fish) are monophyletic, but with the inclusion of the smaller sub-class Sarcopterygii, Osteichthyes is paraphyletic.

This has led to an alternative cladistic classification, splitting the Osteichthyes into two full classes. Osteichthyes is under this scheme monophyletic, as it includes the tetrapods, making it a synonym of the clade Euteleostomi. Most bony fish belong to the ray-finned fish (Actinopterygii).

Actinopterygii Carassius carassius

ray-finned fish
Actinopterygii, or ray-finned fishes, constitute a class or subclass of the bony fishes. The ray-finned fishes are so called because they possess lepidotrichia or "fin rays", their fins being webs of skin supported by bony or horny spines ("rays"), as opposed to the fleshy, lobed fins that characterize the class Sarcopterygii which also possess lepidotrichia. These actinopterygian fin rays attach directly to the proximal or basal skeletal elements, the radials, which represent the link or connection between these fins and the internal skeleton (e.g., pelvic and pectoral girdles). In terms of numbers, actinopterygians are the dominant class of vertebrates, comprising nearly 99% of the over 30,000 species of fish (Davis, Brian 2010). They are ubiquitous throughout freshwater and marine environments from the deep sea to the highest mountain streams. Extant species can range in size from Paedocypris, at 8 mm (0.3 in), to the massive ocean sunfish, at 2,300 kg (5,070 lb), and the long-bodied oarfish, to at least 11 m (36 ft).
Sarcopterygii Coelacanth-bgiu

lobe-finned fish
Sarcopterygii (fleshy fin) or lobe-finned fish constitute a clade (traditionally a class or subclass of fish only, i.e. excluding the tetrapods) of the bony fish, though a strict cladistic view includes the terrestrial vertebrates. The living sarcopterygians are the coelacanths, lungfish, and the tetrapods. Early lobe-finned fishes had fleshy, lobed, paired fins, joined to the body by a single bone.[13] Their fins differ from those of all other fish in that each is borne on a fleshy, lobelike, scaly stalk extending from the body. Pectoral and pelvic fins have articulations resembling those of tetrapod limbs. These fins evolved into legs of the first tetrapod land vertebrates, amphibians. They also possess two dorsal fins with separate bases, as opposed to the single dorsal fin of actinopterygians (ray-finned fish). The braincase of sarcoptergygians primitively has a hinge line, but this is lost in tetrapods and lungfish. Many early lobe-finned fishes have a symmetrical tail. All lobe-finned fishes possess teeth covered with true enamel.

Phylogeny

The phylogeny of living Osteichthyes, including the tetrapods, is shown in the cladogram.[3][14][15][16]

Osteichthyes/
Sarcopterygii
Coelacanthimorpha

Coelacanthiformes Coelacanth flipped

Rhipidistia
Dipnomorpha

CeratodontiformesBarramunda coloured

TetrapodomorphaDeutschlands Amphibien und Reptilien (Salamandra salamdra)

Actinopterygii
Cladistia

PolypteriformesCuvier-105-Polyptère

Actinopteri
Chondrostei

AcipenseriformesAtlantic sturgeon flipped

Neopterygii
Holostei

AmiiformesAmia calva 1908 flipped

LepisosteiformesLongnose gar flipped

Teleostei
Elopocephalai

ElopiformesM.E. Blochii ... Systema ichthyologiae iconibus CX illustratum (Plate 82) (white background)

AlbuliformesPterothrissus gissu1

NotacanthiformesNotacanthus sexspinis1

AnguilliformesAnguilla anguilla1

Osteoglossocephalai
Osteoglossomorpha

Osteoglossiformes F de Castelnau-poissonsPl26 Osteoglossum minus flipped

Hiodontiformes

Clupeocephala
Otomorpha
Clupei

ClupeiformesClupea harengus Gervais

Alepocephali

AlepocephaliformesXenodermichthys copei1 flipped

Ostariophysi
Anotophysa

GonorynchiformesChanos chanos Day

Otophysa

CypriniformesCyprinus carpio3

CharaciformesF de Castelnau-poissonsPl37 (Serrasalmus humeralis)

Gymnotiformes Johann Natterer - Ituí-cavalo (Apteronotus albifrons)

SiluriformesBlack bullhead flipped.jpeg

Euteleosteomorpha

Lepidogalaxiiformes

Protacanthopterygii

ArgentiniformesAlepocephalus rostratus Gervais

Galaxiiformes

Salmoniformes Salmo salar flipped

Esociformes

Stomiatii

OsmeriformesOsmerus mordax flipped

StomiatiformesMelanocetus murrayi (Murrays abyssal anglerfish)

NeoteleosteiZeus faber

Euteleostomi
Neoteleostei
Ateleopodia

Ateleopodiformes

Eurypterygia
Aulopa

Aulopiformes

Ctenosquamata
Myctophata

Myctophiformes

Acanthomorphata
Lampridacea

Lampriformes

Paracanthomorphacea

Percopsiformes

Zeiformes

Stylephoriformes

Gadiformes

Polymixiacea

Polymixiiformes

Euacanthomorphacea

Beryciformes

Holocentriformes

Percomorphaceae

Ophidiiformes

Batrachoidiformes

Gobiaria

Kurtiformes

Gobiiformes

Scombrimopharia

Syngnathiformes

Scombriformes

Carangimopharia
Ovalentaria

Polycentridae

Pholidichthyiformes

Cichliformes

Atheriniformes

Cyprinodontiformes

Beloniformes

Ovalentaria incertae sedis

Mugiliformes

Blenniiformes

Anabantaria

Synbranchiformes

Anabantiformes

Carangaria

Carangaria incertae sedis 1

Carangaria incertae sedis 2

Centropomidae

Pleuronectiformes

Carangiformes

Carangaria incertae sedis 3

Istiophoriformes

Percomorpharia

Eupercaria incertae sedis

Labriformes

Ephippiformes

Lobotiformes

Acanthuriformes

Chaetodontiformes

Spariformes

Lophiiformes

Tetraodontiformes

Uranoscopiformes

Pempheriformes

Centrarchiformes

Perciformes

Whole-genome duplication took place in the ancestral Osteichthyes.[17]

Biology

All bony fish possess gills. For the majority this is their sole or main means of respiration. Lungfish and other osteichthyan species are capable of respiration through lungs or vascularized swim bladders. Other species can respire through their skin, intestines, and/or stomach.[18]

Osteichthyes are primitively ectothermic (cold blooded), meaning that their body temperature is dependent on that of the water. But some of the larger marine osteichthyids, such as the opah,[19][20] swordfish[21][22] and tuna[23][24] have independently evolved various levels of endothermy. Bony fish can be any type of heterotroph: numerous species of omnivore, carnivore, herbivore, filter-feeder or detritivore are documented.

Some bony fish are hermaphrodites, and a number of species exhibit parthenogenesis. Fertilization is usually external, but can be internal. Development is usually oviparous (egg-laying) but can be ovoviviparous, or viviparous. Although there is usually no parental care after birth, before birth parents may scatter, hide, guard or brood eggs, with sea horses being notable in that the males undergo a form of "pregnancy", brooding eggs deposited in a ventral pouch by a female.

Examples

The ocean sunfish is the heaviest bony fish in the world,[25] while the longest is the king of herrings, a type of oarfish. Specimens of ocean sunfish have been observed up to 3.3 metres (11 ft) in length and weighing up to 2,303 kilograms (5,077 lb). Other very large bony fish include the Atlantic blue marlin, some specimens of which have been recorded as in excess of 820 kilograms (1,810 lb), the black marlin, some sturgeon species, and the giant and goliath grouper, which both can exceed 300 kilograms (660 lb) in weight. In contrast, the dwarf pygmy goby measures a minute 15 millimetres (0.59 in).

Arapaima gigas is the largest species of freshwater bony fish. The largest bony fish ever was Leedsichthys, which dwarfed the beluga sturgeon, ocean sunfish, giant grouper, and all the other giant bony fishes alive today.

Comparison with cartilaginous fishes

Cartilaginous fishes can be further divided into sharks, rays and chimaeras. In the table below, the comparison is made between sharks and bony fishes. For the further differences with rays, see sharks versus rays.

Comparison of cartilaginous and bony fishes [26]
Characteristic Sharks (cartilaginous) Bony fishes
Habitat Mainly marine Marine and freshwater
Shape Usually dorso-ventrally flattened Usually bilaterally flattened
Exoskeleton Separate dermal placoid scales Overlapping dermal cosmoid, ganoid, cycloid or ctenoid scales
Endoskeleton Cartilaginous Mostly bony
Caudal fin Heterocercal Heterocercal or diphycercal
Pelvic fins Usually posterior. Mostly anterior, occasionally posterior.
Intromittent organ Males use pelvic fins as claspers for transferring sperm to a female Do not use claspers, though some species use their anal fins as gonopodium for the same purpose
Mouth Large, crescent shaped on the ventral side of the head Variable shape and size at the tip or terminal part of the head
Jaw suspension Hyostylic Hyostylic and autostylic
Gill openings Usually five pairs of gill slits which are not protected by an operculum. Five pairs of gill slits protected by an operculum (a lateral flap of skin).
Type of gills Larnellibranch with long interbranchial septum Filiform with reduced interbranchial septum
Spiracles The first gill slit usually becomes spiracles opening behind the eyes. No spiracles
Afferent branchial vessels Five pairs from ventral aorta to gills Only four pairs
Efferent branchial vessels Nine pairs Four pairs
Conus arteriosus Present in heart Absent
Cloaca A true cloaca is present only in cartilaginous fishes and lobe-finned fishes. In most bony fishes, the cloaca is absent, and the anus, urinary and genital apertures open separately [27]
Stomach Typically J-shaped Shape variable. Absent in some.
Intestine Short with spiral valve in lumen Long with no spiral valve
Rectal gland Present Absent
Liver Usually has two lobes Usually has three lobes
Swim bladder Absent Usually present
Brain Has large olfactory lobes and cerebrum with small optic lobes and cerebellum Has small olfactory lobes and cerebrum and large optic lobes and cerebellum
Restiform bodies Present in brain Absent
Ductus endolymphaticus Opens on top of head Does not open to exterior
Retina Lacks cones Most fish have double cones, a pair of cone cells joined to each other.
Accommodation of eye Accommodate for near vision by moving the lens closer to the retina Accommodate for distance vision by moving the lens further from the retina [28]
Ampullae of Lorenzini Present Absent
Male genital duct Connects to the anterior part of the genital kidney No connection to kidney
Oviducts Not connected to ovaries Connected to ovaries
Urinary and genital apertures United and urinogenital apertures lead into common cloaca Separate and open independently to exterior
Eggs A small number of large eggs with plenty of yolk A large number of small eggs with little yolk
Fertilisation Internal Usually external
Development Ovoviviparous types develop internally. Oviparous types develop externally using egg cases Normally develop externally without an egg case

See also

References

Citations

  1. ^ Bony fishes SeaWorld. Retrieved 2 February 2013.
  2. ^ Jaws, Teeth of Earliest Bony Fish Discovered
  3. ^ a b Betancur-R, Ricardo; et al. (2013). "The Tree of Life and a New Classification of Bony Fishes". PLOS Currents Tree of Life. 5 (Edition 1). doi:10.1371/currents.tol.53ba26640df0ccaee75bb165c8c26288. PMC 3644299. PMID 23653398. Archived from the original on 2013-10-13.
  4. ^ "2009/03/guiyu-oldest-articulated-osteichthyan_26". palaeoblog.blogspot.com. 2009-03-26. Retrieved 2014-01-25.
  5. ^ "Descubrimiento de fósil de pez óseo en China aporta nuevos conocimientos clave sobre origen de los vertebrados_Spanish.china.org.cn". spanish.china.org.cn. Retrieved 2014-01-25.
  6. ^ Zhu, M; Zhao, W; Jia, L; Lu, J; Qiao, T; Qu, Q (2009). "The oldest articulated osteichthyan reveals mosaic gnathostome characters". Nature. 458 (7237): 469–474. Bibcode:2009Natur.458..469Z. doi:10.1038/nature07855. PMID 19325627.
  7. ^ Coates, M.I. (2009). "Palaeontology: Beyond the Age of Fishes". Nature. 458 (7237): 413–414. Bibcode:2009Natur.458..413C. doi:10.1038/458413a. PMID 19325614.
  8. ^ Pharyngula Archived 2012-03-09 at the Wayback MachineScience blogs, 1 April 2009.
  9. ^ Clack, Jennifer A. (27 June 2012). Gaining Ground, Second Edition: The Origin and Evolution of Tetrapods. Indiana University Press. p. 23. ISBN 978-0-253-00537-3. Retrieved 12 May 2015.
  10. ^ Laurin, Michel (2 November 2010). How Vertebrates Left the Water. University of California Press. p. 38. ISBN 978-0-520-94798-6. Retrieved 14 May 2015.
  11. ^ Benton, Michael (4 August 2014). Vertebrate Palaeontology. Wiley. p. 281. ISBN 978-1-118-40764-6. Retrieved 22 May 2015.
  12. ^ Parsons, Alfred Sherwood Romer, Thomas S. (1986). The vertebrate body (6th ed.). Philadelphia: Saunders College Pub. ISBN 978-0-03-910754-3.
  13. ^ Clack, J. A. (2002) Gaining Ground. Indiana University
  14. ^ Betancur-R; et al. (2013). "Complete tree classification (supplemental figure)" (PDF). PLOS Currents Tree of Life (Edition 1). Archived from the original (PDF) on 2013-10-21.
  15. ^ Betancur-R; et al. (2013). "Appendix 2 – Revised Classification for Bony Fishes" (PDF). PLOS Currents Tree of Life (Edition 1).
  16. ^ Ricardo Betancur-R; Edward O. Wiley; Gloria Arratia; Arturo Acero; Nicolas Bailly; Masaki Miya; Guillaume Lecointre; Guillermo Ortí (2017). "Phylogenetic classification of bony fishes". BMC Evolutionary Biology. 17 (1): 162. doi:10.1186/s12862-017-0958-3. PMC 5501477. PMID 28683774.
  17. ^ Dehal, Paramvir; Boore, Jeffrey L. (2005-09-06). "Two Rounds of Whole Genome Duplication in the Ancestral Vertebrate". PLOS Biology. 3 (10): e314. doi:10.1371/journal.pbio.0030314. ISSN 1545-7885. PMC 1197285. PMID 16128622.
  18. ^ Helfman & Facey 1997.
  19. ^ Wegner, Nicholas C., Snodgrass, Owen E., Dewar, Heidi, John, Hyde R. Science. "Whole-body endothermy in a mesopelagic fish, the opah, Lampris guttatus". pp. 786–789. Retrieved May 14, 2015.
  20. ^ "Warm Blood Makes Opah an Agile Predator". Fisheries Resources Division of the Southwest Fisheries Science Center of the National Oceanic and Atmospheric Administration. May 12, 2015. Retrieved May 15, 2015. "New research by NOAA Fisheries has revealed the opah, or moonfish, as the first fully warm-blooded fish that circulates heated blood throughout its body..."
  21. ^ Fritsches, K.A., Brill, R.W., and Warrant, E.J. 2005. Warm Eyes Provide Superior Vision in Swordfishes. Archived 2006-07-09 at the Wayback Machine Current Biology 15: 55−58
  22. ^ Hopkin, M. (2005). Swordfish heat their eyes for better vision. Nature, 10 January 2005
  23. ^ Sepulveda, C.A.; Dickson, K.A.; Bernal, D.; Graham, J.B. (1 July 2008). "Elevated red myotomal muscle temperatures in the most basal tuna species, Allothunnus fallai" (PDF). Journal of Fish Biology. 73 (1): 241–249. doi:10.1111/j.1095-8649.2008.01931.x. Archived from the original (PDF) on February 7, 2013. Retrieved 2 November 2012.
  24. ^ "Tuna — Biology Of Tuna". Retrieved September 12, 2009.
  25. ^ "Mola (Sunfish)". National Geographic. 2010-11-11. Retrieved 28 October 2016.
  26. ^ Based on: Kotpal R. L. (2010) Modern Text Book Of Zoology Vertebrates Archived 2016-04-22 at the Wayback Machine Pages 193. Rastogi Publications. ISBN 9788171338917.
  27. ^ Romer, Alfred Sherwood; Parsons, Thomas S. (1977). The Vertebrate Body. Philadelphia, PA: Holt-Saunders International. pp. 396–399. ISBN 978-0-03-910284-5.
  28. ^ Schwab, IR; Hart, N (2006). "More than black and white". British Journal of Ophthalmology. 90 (4): 406. doi:10.1136/bjo.2005.085571. PMC 1857009. PMID 16572506.

Bibliography

  • Helfman, G.S.; Facey, D.E (1997). The Diversity of Fishes. Blackwell Sciences. ISBN 978-0-86542-256-8
Bait fish

Bait fish are small fish caught for use as bait to attract large predatory fish, particularly game fish. Species used are typically those that are common and breed rapidly, making them easy to catch and in regular supply. Examples of marine bait fish are anchovies, gudgeon, halfbeaks such as ballyhoo, and scad. Some larger fish such as menhaden, flying fish, or ladyfish may be considered bait fish in some circles, depending on the size of the gamefish being pursued.

Freshwater bait fish include any fish of the minnow or carp family (Cyprinidae), sucker family (Catostomidae), top minnows or killifish family (Cyprinodontidae), shad family (Clupeidae), sculpin of the order Osteichthyes and sunfish family (Centrarchidae), excluding black basses and crappies.

Bait fish can be contrasted with forage fish. Bait fish is a term used particularly by recreational fishermen, although commercial fisherman also catch fish to bait longlines and traps. Forage fish is a fisheries term, and is used in that context. Forage fish are small fish that are preyed on in the wild by larger predators for food. The predators can be other larger fish, seabirds and marine mammals. Bait fish, by contrast, are fish that are caught by humans to use as bait for other fish. The terms also overlap in the sense that most bait fish are also forage fish, and most forage fish can also be used as bait fish.

Baitfish can be attracted either via scent, or by using light which actually works by attracting zooplankton, a primary food source for many baitfish, which are then drawn to the light.

Bait fish can also be contrasted with feeder fish. Feeder fish is a term used particularly in the context of fish aquariums. It refers essentially the same concept, small fish that are eaten by larger fish, but adapted for use in a different context.

Bait fish are consumed by larger, aquatic predators. Swimming in ocean water with bait fish can be dangerous, as these fish attract sharks. Bait fish will sometimes use whale sharks as a shield from their other predators such as tuna, as tuna are usually wary of approaching the sharks. The shark cannot attack the bait fish easily, as they constantly swim above them and are too fast for the shark to manoeuvre its mouth into position. However, the sharks eventually dive deep, where the bait fish cannot follow, and as the other predators finally dare attack the stranded bait fish, the shark comes back to eat numerous bait fish who are already preoccupied with the attacking tuna.

There is a bait fish industry in North America, supplying mainly recreational fishermen, worth up to one billion dollars each year.

Blobfish

The blobfish (Psychrolutes marcidus) is a deep sea fish of the family Psychrolutidae. It inhabits the deep waters off the coasts of mainland Australia and Tasmania, as well as the waters of New Zealand.Blobfish are typically shorter than 30 cm (12 in). They live at depths between 600 and 1,200 m (2,000 and 3,900 ft) where the pressure is 60 to 120 times as great as at sea level, which would likely make gas bladders inefficient for maintaining buoyancy. Instead, the flesh of the blobfish is primarily a gelatinous mass with a density slightly less than water; this allows the fish to float above the sea floor without expending energy on swimming. Its relative lack of muscle is not a disadvantage as it primarily swallows edible matter that floats in front of it such as deep-ocean crustaceans.Blobfish are often caught as bycatch in bottom trawling nets.

The popular impression of the blobfish as bulbous and gelatinous is partially an artifact of the decompression damage done to specimens when they are brought to the surface from the extreme depths in which they live. In their natural environment, blobfish appear more typical of their superclass Osteichthyes (bony fish).

Cabonnichthys

Cabonnichthys ("Burns' Cabonne fish") is an extinct genus of Tristichopterid fish that lived in the Late Devonian period (Famennian) of Australia. It has been found in Canowindra and is a medium-sized carnivorous lobe-finned fish.

Chordate

A chordate () is an animal constituting the phylum Chordata. During some period of their life cycle, chordates possess a notochord, a dorsal nerve cord, pharyngeal slits, an endostyle, and a post-anal tail: these five anatomical features define this phylum. Chordates are also bilaterally symmetric; and have a coelom, metameric segmentation, and a circulatory system.

The Chordata and Ambulacraria together form the superphylum Deuterostomia. Chordates are divided into three subphyla: Vertebrata (fish, amphibians, reptiles, birds, and mammals); Tunicata (salps and sea squirts); and Cephalochordata (which includes lancelets). There are also extinct taxa such as the Vetulicolia. Hemichordata (which includes the acorn worms) has been presented as a fourth chordate subphylum, but now is treated as a separate phylum: hemichordates and Echinodermata form the Ambulacraria, the sister phylum of the Chordates. Of the more than 65,000 living species of chordates, about half are bony fish that are members of the superclass Osteichthyes.

Chordate fossils have been found from as early as the Cambrian explosion, 541 million years ago. Cladistically (phylogenetically), vertebrates - chordates with the notochord replaced by a vertebral column during development - are considered to be a subgroup of the clade Craniata, which consists of chordates with a skull. The Craniata and Tunicata compose the clade Olfactores. (See diagram under Phylogeny.)

Cyprininae

The Cyprininae are one of at least 11 subfamilies of cyprinid fish. It contains three genera in its strictest definition but many more are included depending on which authority is defining it, especially if the Labeobarbinae is not considered to be a valid grouping.

Devonosteus

Devonosteus is an extinct genus of prehistoric sarcopterygian or lobe-finned fish.

Euteleostomi

Euteleostomi is a successful clade that includes more than 90% of the living species of vertebrates. Euteleostomes are also known as "bony vertebrates". Both its major subgroups are successful today: Actinopterygii includes the majority of extant fish species, and Sarcopterygii includes the tetrapods.

"Osteichthyes" in the paleontological sense (i.e., "bony vertebrates"), is synonymous with Euteleostomi. However, in ichthyology and Linnaean taxonomy Osteichthyes, literally "bony fish," refers to the paraphyletic group that differs by excluding tetrapods. The name Euteleostomi, coined as a monophyletic alternative that unambiguously includes the living tetrapods, is more widely used in bioinformatics and related fields. The term Euteleostomi comes from Eu-teleostomi, where "Eu-" comes from the Greek εὖ meaning well or good, so the clade can be defined as the living teleostomes.

Euteleostomes originally all had endochondral bone, fins with lepidotrichs (fin rays), jaws lined by maxillary, premaxillary, and dentary bones composed of dermal bone, and lungs. Many of these characters have since been lost by descendant groups, however, such as lepidotrichs lost in tetrapods, and bone lost among the chondrostean fishes. Lungs have been retained in dipnoi (lungfish), and many tetrapods (birds, mammals, reptiles, and some amphibians). In many ray-finned fishes lungs have evolved into swim bladders for regulating buoyancy, while in others they continue to be used as respiratory gas bladders.

Gnathostomata

Gnathostomata are the jawed vertebrates. The term derives from Greek: γνάθος (gnathos) "jaw" + στόμα (stoma) "mouth". Gnathostome diversity comprises roughly 60,000 species, which accounts for 99% of all living vertebrates. In addition to opposing jaws, living gnathostomes have teeth, paired appendages, and a horizontal semicircular canal of the inner ear, along with physiological and cellular anatomical characters such as the myelin sheathes of neurons. Another is an adaptive immune system that uses V(D)J recombination to create antigen recognition sites, rather than using genetic recombination in the variable lymphocyte receptor gene.It is now assumed that Gnathostomata evolved from ancestors that already possessed a pair of both pectoral and pelvic fins. These ancestors, known as antiarchs, were previously thought to not possess pectoral or pelvic fins until recently. In addition to this, some placoderms were shown to have a third pair of paired appendages, that had been modified to claspers in males and basal plates in females--a pattern not seen in any other vertebrate group.The Osteostraci are generally considered the sister taxon of Gnathostomata.It is believed that the jaws evolved from anterior gill support arches that had acquired a new role, being modified to pump water over the gills by opening and closing the mouth more effectively – the buccal pump mechanism. The mouth could then grow bigger and wider, making it possible to capture larger prey. This close and open mechanism would, with time, become stronger and tougher, being transformed into real jaws.

Newer research suggests that a branch of Placoderms was most likely the ancestor of present-day gnathostomes. A 419-million-year-old fossil of a placoderm named Entelognathus had a bony skeleton and anatomical details associated with cartilaginous and bony fish, demonstrating that the absence of a bony skeleton in Chondrichthyes is a derived trait. The fossil findings of primitive bony fishes such as Guiyu oneiros and Psarolepis, which lived contemporaneously with Entelognathus and had pelvic girdles more in common with placoderms than with other bony fish, show that it was a relative rather than a direct ancestor of the extant gnathostomes. It also indicates that spiny sharks and Chondrichthyes represent a single sister group to the bony fishes. Fossils findings of juvenile placoderms, which had true teeth that grew on the surface of the jawbone and had no roots, making it impossible to replace or regrow as they broke or wore down as they grew older, proves the common ancestor of all gnathostomes had teeth and place the origin of teeth along with, or soon after, the evolution of jaws.Late Ordovician-aged microfossils of what have been identified as scales of either acanthodians or "shark-like fishes", may mark Gnathostomata's first appearance in the fossil record. Undeniably unambiguous gnathostome fossils, mostly of primitive acanthodians, begin appearing by the early Silurian, and become abundant by the start of the Devonian.

Ichthyology

Ichthyology (from Greek: ἰχθύς, ikhthys, "fish"; and λόγος, logos, "study"), also known as fish science, is the branch of zoology devoted to the study of fish. This includes bony fish (Osteichthyes), cartilaginous fish (Chondrichthyes), and jawless fish (Agnatha). While a large number of species have been discovered, approximately 250 new species are officially described by science each year. According to FishBase, 33,400 species of fish had been described by October 2016.

List of animal classes

The following is a list of the classes in each phylum of the kingdom Animalia. There are 107 classes of animals in 33 phyla in this list. However, different sources give different numbers of classes and phyla. For e.g, Protura, Diplura, and Collembola are often considered to be the three orders in the class Entognatha. This list should by no means be considered complete and authoritative and should be used carefully.

List of chordate orders

This page contains a list of all of the classes and orders that are located in the Phylum Chordata.

List of marine bony fishes of South Africa

This is a sublist of the List of marine fishes of South Africa for bony fishes recorded from the oceans bordering South Africa.

This list comprises locally used common names, scientific names with author citation and recorded ranges. Ranges specified may not be the entire known range for the species, but should include the known range within the waters surrounding the Republic of South Africa.

List ordering and taxonomy complies where possible with the current usage in Wikispecies, and may differ from the cited source, as listed citations are primarily for range or existence of records for the region.

Sub-taxa within any given taxon are arranged alphabetically as a general rule.

Details of each species may be available through the relevant internal links. Synonyms may be listed where useful.

Osteichthyes (), popularly referred to as the bony fish, is a diverse taxonomic group of fish that have skeletons primarily composed of bone tissue, as opposed to cartilage. The vast majority of fish are members of Osteichthyes, which is an extremely diverse and abundant group consisting of 45 orders, and over 435 families and 28,000 species. It is the largest class of vertebrates in existence today.

The group Osteichthyes is divided into the ray-finned fish (Actinopterygii) and lobe-finned fish (Sarcopterygii). The oldest known fossils of bony fish are about 420 million years old, which are also transitional fossils, showing a tooth pattern that is in between the tooth rows of sharks and bony fishes.

List of prehistoric bony fish genera

This List of prehistoric bony fish is an attempt to create a comprehensive listing of all genera from the fossil record that have ever been considered to be bony fish (class osteichthyes), excluding purely vernacular terms. The list includes all commonly accepted genera, but also genera that are now considered invalid, doubtful (nomina dubia), or were not formally published (nomina nuda), as well as junior synonyms of more established names, and genera that are no longer considered members of osteichthyes.

This list includes 1,386 generic names.

Extinct genera are marked with a dagger (†).

Extant genera are bolded.

Lists of organisms by population

This is a collection of lists of organisms by their population. While most of the numbers are estimates, they have been made by the experts in their fields. Species population is a science falling under the purview of population ecology and biogeography. Individuals are counted by census, as carried out for the piping plover; using the transect method, as done for the mountain plover; and beginning in 2012 by satellite, with the emperor penguin being first subject counted in this manner.

Lungfish

Lungfish are freshwater rhipidistian fish belonging to the subclass Dipnoi. Lungfish are best known for retaining characteristics primitive within the Osteichthyes, including the ability to breathe air, and structures primitive within Sarcopterygii, including the presence of lobed fins with a well-developed internal skeleton.

Today there are only six known species of lungfish, living only in Africa, South America and Australia. The fossil record show that lungfish were abundant since the Triassic. While vicariance would suggest this represents an ancient distribution limited to the Mesozoic supercontinent Gondwana, the fossil record suggests advanced lungfish had a widespread freshwater distribution and the current distribution of modern lungfish species reflects extinction of many lineages subsequent to the breakup of Pangaea, Gondwana and Laurasia. Lungfish have historically been referred to as salamanderfish, but this term more often refers to Lepidogalaxias salamandroides.

Mandageria

Mandageria fairfaxi (Pronunciation: Man-daj-ee-ree-a fair-fax-i) is an extinct lobe-finned fish that lived during the Late Devonian period (Frasnian – Famennian). It is related to the much larger Hyneria; although Mandageria was smaller, it probably hunted in the same way.

The generic epithet, Mandageria, refers to the Mandagery Sandstone formation near Canowindra, Australia, where the fossils were found. The specific epithet, fairfaxi, honors the philanthropist James Fairfax. M. fairfaxi is the state fossil emblem for New South Wales.

Muranjilepis

Muranjilepis is an extinct genus of prehistoric sarcopterygians or lobe-finned fish.

Teleostomi

Teleostomi is an obsolete clade of jawed vertebrates that supposedly includes the tetrapods, bony fish, and the wholly extinct acanthodian fish. Key characters of this group include an operculum and a single pair of respiratory openings, features which were lost or modified in some later representatives. The teleostomes include all jawed vertebrates except the chondrichthyans and the extinct class Placodermi.

Recent studies indicate that Osteichthyes evolved from placoderms like Entelognathus, while acanthodians are more closely related to modern chondrichthyes. Teleostomi, therefore, is not a valid, natural clade, but a polyphyletic group of species.The clade Teleostomi should not be confused with the similar-sounding fish clade Teleostei.

Thursius

Thursius is a genus of prehistoric lobe-finned fish.

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